Recovery of End-Of-Life Wood-Plastic Composites (WPC) Products: Influence of Wastes Fields Nature and of a Compatibilizer on Recycled WPC Bending Properties

A mechanical recovery approach is adopted for two polyethylene (PE) based wood-plastics composites (WPCs) wastes fields, with varying ageing degrees. On the one hand, CDP0 consists of defective decking boards in appearance, which cannot be commercialized. On the other hand, FDV0 is made of end-of-life decking boards, exposed for about 10 years outside. CDP0 and FDV0 are first ground, and then reincorporated with an unaged WPC, called WPC-PE0, through extrusion to generate new profiles. A compatibilizer (maleic anhydride grafted polyethylene (PE-g-MA)) is also used to improve processing and mechanical properties of final profiles. The maleic anhydride percentage (MAH%) in PE-g-MA differ, as well as the PE-g-MA content (2 and 4 wt% relative to the wood flour weight). The bending properties are recovered for both CDP0 and FDV0, when reincorporated at 50 wt% with WPC-PE0. Moreover, CDP0 can be recycled at 100 wt%. Unfortunately, the compatibilizers do not improve the flexural strengths of the composites. However, they help the wood flour dispersion within the matrix during processing.

Automated summary

This study adopts a mechanical recovery approach to handle waste polyethylene-based wood-plastic composites, and successfully recovers the bending properties of the waste material through reprocessing and the addition of compatibilizers, although the flexural strengths of the composites are not improved significantly.